DESCRIPTION

These functions provide an interface to mouse events from
ncurses(3X).
Mouse events are represented by KEY_MOUSE
pseudo-key values in the wgetch input stream.

To make mouse events visible, use the mousemask function.
This will set
the mouse events to be reported.
By default, no mouse events are reported.
The function will return a mask to indicate which of the specified mouse events
can be reported; on complete failure it returns 0.
If oldmask is non-NULL,
this function fills the indicated location with the previous value of the given
window's mouse event mask.

As a side effect, setting a zero mousemask may turn off the mouse pointer;
setting a nonzero mask may turn it on.
Whether this happens is device-dependent.

Here are the mouse event type masks which may be defined:

Name

Description

BUTTON1_RELEASED

mouse button 1 up

BUTTON1_CLICKED

mouse button 1 clicked

BUTTON1_DOUBLE_CLICKED

mouse button 1 double clicked

BUTTON1_TRIPLE_CLICKED

mouse button 1 triple clicked

BUTTON2_PRESSED

mouse button 2 down

BUTTON2_RELEASED

mouse button 2 up

BUTTON2_CLICKED

mouse button 2 clicked

BUTTON2_DOUBLE_CLICKED

mouse button 2 double clicked

BUTTON2_TRIPLE_CLICKED

mouse button 2 triple clicked

BUTTON3_PRESSED

mouse button 3 down

BUTTON3_RELEASED

mouse button 3 up

BUTTON3_CLICKED

mouse button 3 clicked

BUTTON3_DOUBLE_CLICKED

mouse button 3 double clicked

BUTTON3_TRIPLE_CLICKED

mouse button 3 triple clicked

BUTTON4_PRESSED

mouse button 4 down

BUTTON4_RELEASED

mouse button 4 up

BUTTON4_CLICKED

mouse button 4 clicked

BUTTON4_DOUBLE_CLICKED

mouse button 4 double clicked

BUTTON4_TRIPLE_CLICKED

mouse button 4 triple clicked

BUTTON5_PRESSED

mouse button 5 down

BUTTON5_RELEASED

mouse button 5 up

BUTTON5_CLICKED

mouse button 5 clicked

BUTTON5_DOUBLE_CLICKED

mouse button 5 double clicked

BUTTON5_TRIPLE_CLICKED

mouse button 5 triple clicked

BUTTON_SHIFT

shift was down during button state change

BUTTON_CTRL

control was down during button state change

BUTTON_ALT

alt was down during button state change

ALL_MOUSE_EVENTS

report all button state changes

REPORT_MOUSE_POSITION

report mouse movement

Once a class of mouse events have been made visible in a window,
calling the wgetch function on that window may return
KEY_MOUSE as an indicator that a mouse event has been queued.
To read the event data and pop the event off the queue, call
getmouse.
This function will return OK if a mouse event
is actually visible in the given window, ERR otherwise.
When getmouse returns OK, the data deposited as y and
x in the event structure coordinates will be screen-relative character-cell
coordinates.
The returned state mask will have exactly one bit set to
indicate the event type.
The corresponding data in the queue is marked invalid.
A subsequent call to getmouse will retrieve the next older
item from the queue.

The ungetmouse function behaves analogously to ungetch.
It pushes
a KEY_MOUSE event onto the input queue, and associates with that event
the given state data and screen-relative character-cell coordinates.

The wenclose function tests whether a given pair of screen-relative
character-cell coordinates is enclosed by a given window, returning TRUE
if it is and FALSE otherwise.
It is useful for determining what subset of
the screen windows enclose the location of a mouse event.

The wmouse_trafo function transforms a given pair of coordinates
from stdscr-relative coordinates
to coordinates relative to the given window or vice versa.
Please remember, that stdscr-relative coordinates are not always identical
to window-relative coordinates due to the mechanism to reserve lines on top
or bottom of the screen for other purposes
(see the ripoffline() and slk_init calls, for example).
If the parameter to_screen is TRUE, the pointers
pY, pX must reference the coordinates of a location
inside the window win.
They are converted to window-relative coordinates and returned
through the pointers.
If the conversion was successful, the function returns TRUE.
If one of the parameters was NULL or the location is
not inside the window, FALSE is returned.
If to_screen is
FALSE, the pointers pY, pX must reference window-relative
coordinates.
They are converted to stdscr-relative coordinates if the
window win encloses this point.
In this case the function returns TRUE.
If one of the parameters is NULL or the point is not inside the
window, FALSE is returned.
Please notice, that the referenced coordinates
are only replaced by the converted coordinates if the transformation was
successful.

The mouse_trafo function performs the same translation
as wmouse_trafo,
using stdscr for win.

The mouseinterval function sets the maximum time (in thousands of a
second) that can elapse between press and release events for them to
be recognized as a click.
Use mouseinterval(0) to disable click resolution.
This function returns the previous interval value.
Use mouseinterval(-1) to obtain the interval without altering it.
The default is one sixth of a second.

The has_mouse function returns TRUE if the mouse driver has been
successfully initialized.

Note that mouse events will be ignored when input is in cooked mode, and will
cause an error beep when cooked mode is being simulated in a window by a
function such as getstr that expects a linefeed for input-loop
termination.

RETURN VALUE

getmouse and ungetmouse
return the integer ERR upon failure or OK
upon successful completion.

getmouse

returns an error.
If no mouse driver was initialized, or
if the mask parameter is zero,
it also returns an error if no more events remain in the queue.

ungetmouse

returns an error if the FIFO is full.

mousemask
returns the mask of reportable events.

mouseinterval
returns the previous interval value, unless
the terminal was not initialized.
In that case, it returns the maximum interval value (166).

wenclose and wmouse_trafo
are boolean functions returning TRUE or FALSE depending
on their test result.

PORTABILITY

These calls were designed for ncurses(3X), and are not found in SVr4
curses, 4.4BSD curses, or any other previous version of curses.

The feature macro NCURSES_MOUSE_VERSION is provided so the preprocessor
can be used to test whether these features are present.
If the interface is changed, the value of NCURSES_MOUSE_VERSION will be
incremented.
These values for NCURSES_MOUSE_VERSION may be
specified when configuring ncurses:

The order of the MEVENT structure members is not guaranteed.
Additional fields may be added to the structure in the future.

Under ncurses(3X), these calls are implemented using either
xterm's built-in mouse-tracking API or
platform-specific drivers including

Alessandro Rubini's gpm server
FreeBSD sysmouse
OS/2 EMX

If you are using an unsupported configuration,
mouse events will not be visible to
ncurses(3X) (and the mousemask function will always
return 0).

If the terminfo entry contains a XM string,
this is used in the xterm mouse driver to control the
way the terminal is initialized for mouse operation.
The default, if XM is not found,
corresponds to private mode 1000 of xterm:

\E[?1000%?%p1%{1}%=%th%el%;

The z member in the event structure is not presently used.
It is intended
for use with touch screens (which may be pressure-sensitive) or with
3D-mice/trackballs/power gloves.

BUGS

Mouse events under xterm will not in fact be ignored during cooked mode,
if they have been enabled by mousemask.
Instead, the xterm mouse
report sequence will appear in the string read.

Mouse events under xterm will not be detected correctly in a window with
its keypad bit off, since they are interpreted as a variety of function key.
Your terminfo description should have kmous set to "\E[M"
(the beginning of the response from xterm for mouse clicks).
Other values for kmous are permitted,
but under the same assumption,
i.e., it is the beginning of the response.

Because there are no standard terminal responses that would serve to identify
terminals which support the xterm mouse protocol, ncurses assumes that
if your $TERM environment variable contains "xterm",
or kmous is defined in
the terminal description, then the terminal may send mouse events.